After the unusually strong summer wave of bird flu in wild birds, the expert Timm Harder sees signs of a certain immunity among the animals in the previously weak autumn and winter wave. From the beginning of October until just before Christmas, fewer than 90 cases were registered nationwide, says the head of the national reference laboratory for avian influenza at the Friedrich Loeffler Institute (FLI) near Greifswald. “That’s very little compared to last year.” There were several hundred.
“So one wonders what can be the cause of this. Unfortunately, we don’t have a binding answer to that either.” But one hopes that the migratory birds have brought a certain immunity with them. The current virus variant has been dominant for a long time, namely since spring 2021. “That is one of the main points on which we base our hope.” Antibodies have also been found in living animals. Widespread spread of the virus between October 2021 and March 2022 could have promoted immunity. According to Harder, the rate of infection in wild birds in Europe was also below the level of previous years.
Nevertheless, the ongoing bird flu epidemic is considered the largest observed in Europe to date, as the European Food Safety Authority announced last Tuesday. Due to the unusually high incidence of infection last summer, the epidemics, which normally concentrate on the cold season, could not be clearly separated from one another.
For the first time, such a wave reached South America in autumn, said Harder. For example, there are cases with pelicans and poultry farms. Peru, Venezuela, but also Ecuador and Colombia are affected. “Brazil certainly has the greatest interest in fighting the virus.” There are still no known cases in the country. But it is the largest chicken meat exporter in the world. “There is certainly a red alert.” Only the continents of Australia and Antarctica are not affected. Looking to Antarctica, he expressed concern that the virus could jump from South America. Then even the penguin stocks there would be in danger.
